^(18)F-FDG的稳定性及提高稳定性的方法

Stability and the Improved Methods of ^(18)F-FDG

本工作研究了常规制备的大剂量、高浓度18F-FDG的稳定性,并在产品中添加稳定剂乙醇或对已部分分解的产品进行再纯化,以提高18F-FDG的放化纯度。结果显示,当18F-FDG产品浓度高于6 TBq/L时,放置4 h,其放化纯度<95%;浓度大于7.4 TBq/L时,添加体积分数为0.1%的乙醇后,能明显降低18F-FDG的分解,6 h后放化纯度>95%;已分解的18F-FDG经再纯化后,放化纯度>99%。Micro PET/CT大鼠显像表明,采用已分解的18F-FDG对大鼠进行显像,其股骨有明显摄取;对其进行再纯化处理后对大鼠显像,大鼠股骨无放射性摄取。以上结果表明,高浓度的18F-FDG有效时间小于4 h;添加0.1%乙醇可明显减慢高浓度18F-FDG分解,而再纯化方法可以彻底除去分解的放射性杂质。为保证18F-FDG质量,将添加稳定剂和再纯化两种方法联合使用,保证产品放化纯度的同时还可提高18F-FDG的利用率。

To study the stability of ^18F-FDG with routinely synthesis at high radio-dose and high radioconcentration,18F-FDG was added 0.1% ethanol or repurification by solid-phase extraction for radiolytic ^18F-FDG to improve its radiochemical purity（RCP）.The results showed that the RCP declined from 99% to 95% within 4 h at 6 TBq/L for room temperature（RT）.The radiolysis could be depressed with 0.1% ethanol,the RCP could be over 95% even if the radioactivity concentration was 7.4 TBq/L at RT for 6 h.The repurification method could improve the RCP of ^18F-FDG from 80% to 99%.Micro PET/CT imagings of normal rats showed that the vertebra had high uptake with radiolytic ^18F-FDG because of impurity.There were no radioactivity uptaking in bone with repuification of 18F-FDG.It indicated that 0.1% ethanol could be used as stabilizers for 18F-FDG to improve the RCP when ^18F-FDG had high radio-dose and high radioconcentrtion.The radiolytic 18F-FDG could be repurified by solid-phase extraction to remove the radio-impurity.The method of added 0.1% thanot could be combined with repurification method to assure the RCP of ^18F-FDG for over 95% at any given time andradiodose or contcentrayion.